Hylaeus modestus

A female Yellow-faced Bee (Hylaeus modestus)
OH how I WISHED the flash hadn't been slowing down.
I saw a couple of these...but with my flash failing, this is the best shot I got of either of them.

LOL! I'd swear they were a couple - they arrived together, worked over flowers very close to each other and left together.
Another reason I said couple is these bees are sexually dimorphic - meaning the sexes look slightly different.
With H. modestus, the female's face has a single pair of short vertical yellow bars beside their large compound eyes - kinda like partial mascara lines. bugguide.net/node/view/797599
For the males, the yellow is a full face mask that covers from one large compound eye to the other and from the base of the antenna to the mouth.
bugguide.net/node/view/532713

The flash failed to fire on shot right after this, but when I cranked the settings, I know this was definitely a female.
I never got a good shot of the male that was with her.

This is the upper right shot in